431.6 on stock internals.

[Roy]

Thats a fair call, but the injector duty cycle has no idea what the fuel rail pressure is, and that can account for why the A/F ratios being ok, as the ECU doesnt have any closed loop mechanism on the duty cycle does it? I mean it doesnt retard boost etc when duty cycle gets over say 95%.

Duty cycle is displayed purely as a tuning aid, and as long as A/F are ok on the dyno's sensor/readout then all is ok.

[GTS-t VSPEC]

Roy, Yes that's true, and I think it is how all of the aftermarket ECU's work. The increased fuel pressure is allowing us to push further than most people, but there are some who are using Wolfs and getting 350rwhp with no rising rate regulator.

[R31Nismoid]

Rightyo... i knew i saw it someplace.

Im back with some actual calculations (hope the are the right ones or me gonna look silly)

From RS500 - He helped me at one stage before.

Use this as a rule of thumb when working out fuel/hp delivery from injectors.

HP = cc per min / 5

therefore,

HP = 370cc / 5 = 74hp per injector

Now this in Engine we are talking about dont forget...

74 x 6 = 440hp (330kw) So you can make 440 HP at the motor end of things wth stock injectors (agreed?)

You are making 431hp at the wheels... Not at the engine.

And just a rising rate reg has got you that far?

To continue this good discussion, does anyone know the loss of power from motor to wheels in an R33 ?

If so... please provide and i'll go away and do some more sums.

Dont shoot me if my calculations are wrong... i've tried to make sure the numbers are right.

By all means correct if i am wrong

[GTS-t VSPEC]

Nismoid, I'm not sure if you'll get a definate answer on the drivetrain losses, you'll get answers from 15-30%.

[Guest INASNT]

INASNT, I will take it down on the 22nd of November, wait till then

u expect us to abuse you until till???

[R31Nismoid]

Originally posted by GTS-t VSPEC

Nismoid, I'm not sure if you'll get a definate answer on the drivetrain losses, you'll get answers from 15-30%.

Yeah i know... I usually go 20-30%

Maybe someone out there has..........

Engine dyno'd the car, then had it on a chassis soon after by chance?

Asking a bit much but you never know.

[GTS-t VSPEC]

INASNT, I'll run my car down the plex when you have yours back on the road:shake:

[N I B]

I think Pauls GTS has about 460 flywheel, 30% loss is just not true.

[Sydneykid]

Hi R31Nismoid, it has been our experience that a standard R33 GTST looses about 60 to 65 kw through the drive train on Dyno Dynamics roller dyno. Remembering that the 431.6 was rhhp (rhhp = on hub dyno) which seem to loose about 10 to 15 kw less than a roller dyno. Thus confirming the 411 rwhp previously reported.

So 431.6 rhhp (or 411 rwhp) would be around 500 bhp (bhp = at the engine).

Hope that enables R31Nismoid to finish the calculations.

[GTS-t VSPEC]

Sydneykid, Out of interest how were you able to calculate the drivetrain losses?

[R31Nismoid]

Originally posted by Sydneykid

Hope that enables R31Nismoid to finish the calculations.

It should

All theoretically of course.

I'm busy at work today... so it'll be done tomorrow morning

-ash

[Sydneykid]

Hi GTS-t VSPEC, "you asked how were you able to calculate the drivetrain losses?"

I didn't calculate them, it is real data built up from experiences on our dyno from over 20 Skylines. Many of which were standard when they first went on the rollers. The only assumption is that Nissan quote accurate engine kw figures for GTST's. Of course they don't for GTR's, they are all understated to comply with the 206 kw gentlemen's agreement.

Plus we have run a couple of engines on the engine dyno and then ran them up on the chassis dyno. This confirmed the relativity of the standard Nissan power figures for the GTST's.

I have also back to back tested our Dyno Dynamics (roller) with a Dynojet (hub) on the same day using the same car. Free demo as they were trying to sell us one, nearly bought it too.

So no guesses here, real world experiences and factual data, you can't run a circuit race team any other way.

Hope that clarifies

[RNS11Z]

Gtst-Vspec: How far are you going to try and push your car?? I believe the stock rods start break once your over the 450rwhp mark. Pretty figures you have there. But could you please answer my question to "What is the size of your exhaust housing on the GT30. Is .82??".

Thanks

Harun

[GTS-t VSPEC]

Sydneykid, Thanks for that:D

RNS11Z, I think it's smaller than that, 0.68? I'm planning forged pistons and rods, and hopig to have 500rwhp as a daily driver:D

[RNS11Z]

Good luck with getting that figure. Should be awesome to drive.

My old turbo was a .82. With 1.7bar it made 421rwhp. I know of many other skylines using a similar turbo to my old one that make similar powers at similar boost levels. I just dont seem to understand how you are able to make more power with less boost & standard injectors. I should come for a drive your way.

[GTS-t VSPEC]

The 400+ at the wheels is less exciting than the 360 tune, as it has too much fuel and very little timing, so although it makes good power it is a slow ramp up, just to save the stock pistons:D

[Guest INASNT]

0.68 rear seems a bit small to be making those high rwhp at that low boost!! hmmmmmmmmm

[R31Nismoid]

Originally posted by Sydneykid

Hi  R31Nismoid, it has been our experience that a standard R33 GTST looses about 60 to 65 kw through the drive train on Dyno Dynamics roller dyno.  Remembering that the 431.6 was rhhp (rhhp = on hub dyno) which seem to loose about 10 to 15 kw less than a roller dyno.  Thus confirming the 411 rwhp previously reported.

So 431.6 rhhp (or 411 rwhp) would be around 500 bhp (bhp = at the engine).

Hope that enables R31Nismoid to finish the calculations.

I'm back Ok, what i have is this. 500Hp.

The figures inputted are in Bold.

HP = Xcc / 5 = hp Per injector.

HP = 417 / 5 = 83 hp Per Injector

So the stock injectors are being pushed to 417 cc per injector.

Now this is where i get buggered, i think the increase is 11.3% per injector (which is across all injectors).

Correct me on the percentage if i am wrong. I cant remember how to work it out :confused:

So that's the math part done, correctly i hope

ash

[Steve]

I got 112.7% for the injectors, divide 417 by 370 and multiply by 100. BUT

If the 417 is at 90% duty cycle (which I think? Paul mention the injectors were at), 100% would be 463 which is 125% approx of the 370cc injectors (remebering that 370 is 100% of the stock injectors)

IF my maths is right.

[R31Nismoid]

Originally posted by Steve

I got 112.7% for the injectors,  divide 417 by 370 and multiply by 100.  BUT

Oh... i forgot the multipy by 100... poo!

But though... it's a 12-13% increase over stock at the end of the day. i did a round off there steve

Is there agree-ance there on that then?

As you already start with 100% ability to use the injectors.